As you climb the narrow steps to the second level of 531 E. Ohio St., the years fall away. Sweet fiddle music from Civil War days muffles street sounds and thick red carpet softens your footsteps. White lace curtains and red velvet drapes trimmed with gold brocade filter the light. Chairs before a burnished wood fireplace invite you to linger and look.

Bruce Klein views a photo through a stereo viewer at Photo Antiquities, the North Side museum he created to display 19th-century photography. (John Beale, Post-Gazette)

Looking carefully is what you must do at Photo Antiquities. Images of American Indians, well-to-do families, mug shots and babies resting on lace pillows gaze back at you from well-lit glass shelves. Queen Victoria is nestled among other royalty but next to common folk. They are sober faces, not smiling, because a five-minute exposure time was too long for anyone to hold a smile.

But Bruce Klein has saved these photos from the trash heap or gradual deterioration. With his curator, Frank Watters, Klein has traveled the country to gather half a million photos, tintypes, daguerreotypes, ambrotypes, albumen prints, slides and more than 1,000 old cameras and pieces of photographic equipment. Klein and Watters say it is the largest public display of 19th-century photography in the United States.

"If you go to the Smithsonian, you won't see this many old photos on display," says Klein. "The museum directors assume there is not that much interest in them."

But Klein, 44, has found enough interest in his collection to justify plans to move it to a new location, 10 times as large. In a year or two, Photo Antiquities will complete its move to the Hartman Building, an old ice cream store at 1212 Madison Ave., Spring Garden. Klein is looking forward to the additional space so that the entire collection can be displayed at once, rather than on a weekly rotation. Moving will also mean space for a global connection.

"We want to have a sophisticated Internet application that will allow us to send a good quality photo of, say, Louis Jacques Monde Daguerre, the Frenchman who invented the first photographic method, to, perhaps, the Getty Museum in Los Angeles."

Neighborhood connections will be enhanced, too. Klein plans to hire people from the North Side neighborhood and offer classes to teach young people about the early methods of photography.

"The people in Spring Garden have welcomed us with open arms," he says.

Following in the footsteps of his father, Bernie Klein, Bruce Klein is the owner of Bernie's Photo, Pittsburgh Custom Dark Room and the Pittsburgh Camera Exchange. But antique photos are more than a hobby for him. They're a mission.

"Photos freeze a moment in time," he says, noting that they are sometimes the only record of that moment. It was not until 1890 that a negative could be created.

His collection began with a tintype gathered here or there at a flea market.

"I like to look at them," he says.

So did other people who came into his office. Klein started with a small display above the camera shop. It eventually grew to fill the space.

Klein found a kindred spirit one day in March 1990, when Watters came into Bernie's Camera to leave some film to be developed.

"I saw a sign in the window, 'Help Wanted,' and came back in a suit and a tie to talk to Bruce Klein," Watters says, speaking in his soft Irish accent. "We went around a bit about the accent, which was much stronger then, and my experience, and I got the job, working the counter."

Watters, 36, had studied photography in Ireland and shared Klein's passion for historical photography. He became manager of the Camera Exchange, where old cameras come and go, and curator of Photo Antiquities as well.

The museum's collection grew by leaps and bounds when Klein bought out a large collection in Boston.

" Frank Watters and I came back with a U-Haul full of photos," says Klein.

In the past 10 years, Klein and Watters have traveled the country, viewing collections, attending auctions and going to photography shows.

"It's like trading baseball cards," Watters says. "I'll give you one of my Bradys for one of your Gardners," referring to Civil War photographers Mathew Brady and Alexander Gardner.

One buying trip changed Watters' life. The two were in Gettysburg when he found the monument to Union Gen. Michael Corcoran and the Irish Brigade.

"It made the hair stand up on my skin, and it still does to think about it," he says.

For Watters, the brigade's bravery and patriotism were his missing link between America and Ireland.

"I had left Ireland and resigned myself to living, dying and being buried here. But I felt a need to have something of Ireland to pass on to my son and my daughter."

These days, Watters wears Corcoran's uniform and tells his story when he visits schools throughout the area, as part of the museum's outreach program.

"We celebrate Corcoran's birthday, and my young children know more about American history than most high school seniors," Watters says.

Photo Antiquities' third floor is devoted to the work of Brady and other images of the Civil War. Although Brady was the most famous wartime photographer, many of the pictures were taken by assistants like Gardner, since Brady was almost blind from inhaling mercury fumes while making daguerreotypes.

"In the new museum, we'll have a Brady Room," says Klein.

The museum's current home was once a house, so it has nooks and crannies and even an atrium converted to display areas. Klein, Watters and their small staff take great pains to make sure the images are both accessible and well-preserved. Klein bought the oak library shelving from a school in the South Hills and installed special conservation glass that filters out damaging ultraviolet light. Sometimes, the wooden shelves were replaced with glass both above and below for better viewing. Every photo is mounted on archival mat board and framed with conservation glass.

The air is regulated to a constant temperature of 68 to 70 degrees and humidity of 45 percent, the correct conditions for archival preservation. An air changer replaces the air in these rooms every hour, so that dust brought in on people's feet is filtered out.

In the Pittsburgh Room, there are photos on the wall, behind glass and propped on the floor, of Polish Hill, Fifth Avenue, the Allegheny County Courthouse, the construction of Forbes Field, burning barges set afire by the 1892 Homestead strikers, and Dimlings Bar and Restaurant on Market Square.

Other special-interest areas include photogravures by the famed American Indian photographer Edward Curtis, which line the staircase to the third floor.

More than a museum, Photo Antiquities can do digital restoration and museum-quality matting and framing of old photos. If you have a photo of an unknown relative, Klein and his staff can help you figure out who it is.

"We go backwards," Klein says. "We can tell you when the photo was made, and estimate the age of the person. Then you go back in your family tree and see who was that age then."

Klein has never lost his youthful fascination with old photos -- and the "moments in time" they capture. "Now, look at this face," he says, pointing to an 1880 photo taken on the North Side. An African-American man wearing a straw hat and overalls looks directly at the viewer. He is very old, with high cheekbones and a handsome bearded face. Klein knows nothing about him. Did he come North after the Emancipation? Or did he come on the Underground? We can only speculate.

"That's one of my favorites,' says Klein.

Photo Antiquities, 531 E. Ohio St., is open 10 a.m. to 5 p.m. Mondays through Saturdays. Admission is $4, $3 for students and seniors, $2 for children ages 6 to 12. Phone: 412-231-7881.